Why do my windscreen washer jets keep getting blocked?

Tomorrow I am taking my car in for the third time to have the screen washers fixed/unblocked. The second time I was told that I was using the wrong screenwash, they fixed the problem and refilled the screenwash only for a month later the same problem to reappear. I haven't had to refill the reservoir since they last had the car. I am naturally annoyed with this as every time it happens I have to wait a week or so to get a booking, does this mean that I am in fact driving an illegal car if I can't clean the screen? What should I insist on?

Asked on 28 June 2018 by Barry Vanderpant

Answered by Honest John
This is usually caused by sludge in the washer reservoir blocking the mesh filter for the pump. A quick fix is to get a hosepipe, shove it right into the bottom of the washer reservoir, hold it there, then get someone else to turn on the tap. That blasts all the crud out of the reservoir. However you should also check the pipes from the screenwash reservoir to the jets on the bonnet. If they are kinked or otherwise trapped in the bonnet hinges, then screenwash cannot get through.
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